An input device can be manipulated by a user to generate input data in a computer system. Typically, an input device is positioned on a surface and moved relative to that surface, but other forms of input devices operating in different fashions are also available. The operations performed on an input device generally correspond to moving a navigational object (e.g., a cursor) and/or making selections on a display screen. There are many kinds of electronic input devices, such as buttons or keys, pens, digitizing pads, game controllers, trackballs, touch screens, touch pads, mice, and the like. A “mouse” is a common type of input device that functions as a pointing device for a computer by detecting motion imparted by a user. The mouse's motion is typically translated into motion of a navigational object (e.g., cursor) on a graphical user interface (GUI) provided on a display screen. A mouse generally comprises a small case, held in a user's hand, with one or more input buttons. Additionally, a mouse may have other elements, such as a scroll wheel, that allow a user to perform enhanced operations.
When tracking the motion of an electronic input device, there can be a wide range of motions from large coarse motions to small fine motions. For example, a user may perform a large, coarse motion with the input device to move a navigational object from one side of a graphical display to another side of the graphical display. In contrast, a user may perform a small, fine motion with the input device to move the navigational object a relatively small number pixels (e.g., 1 to 100 pixels). A user may want to move a navigational object a relatively small number of pixels when homing in on a small target area, such as a space between two adjacent characters in a text file. However, many conventional mouse-type input devices slip or jerk when the user attempts to move the input device in small increments due to static/kinetic friction transitions. This can cause unstable control of the navigational object.
Accordingly, fine control of a navigational object using an electronic input device can be a difficult challenge when the input device is also used for coarse cursor control.